1. Field of the Invention
The present invention relates to a technical field of a substrate processing apparatus for performing heat processing and cool processing for substrates such as semiconductor wafers and the like.
2. Description of the Related Art
In semiconductor device fabrication, for example, a layer insulation film is formed by, for example, an SOD (Spin on Dielectric) system. In the SOD system, a wafer is spin-coated with a coating film, and chemical processing, heat-processing, or the like is applied thereto, whereby a layer insulation film is formed.
When a layer insulation film is formed by, for example, a sol-gel method, an insulation film material, for example, a solution in which colloids of TEOS (tetraethoxysilane) are dispersed in an organic solvent is supplied onto a semiconductor wafer (hereinafter called xe2x80x9cthe waferxe2x80x9d) at first. Next, gelling processing is performed for the wafer supplied with the solution, and then replacement of the solvent is performed. Subsequently, the wafer with the solvent being replaced is heat-processed.
In these series of process steps, various kinds of heat-processing are performed. These kinds of heat-processing are generally performed by placing a wafer on a plate for heat-processing, however, when a wafer is directly placed on the plate, the wafer is adversely affected by static electricity. For this and other reasons, a wafer is heat-processed with a gap being formed between the wafer and the plate by a gap forming member being placed on the plate.
Since an outside air enters a processing chamber when a wafer is carried into and out of the processing chamber, the processing chamber in which the plate is placed varies in temperature by about 100xc2x0 C. Therefore, the plate made of ceramics repeatedly expands and shrinks, whereby the plate is extremely worn out and sometimes cracks.
An object of the present invention is to provide a substrate processing apparatus in which a plate with less occurrence of cracking and increased durability is placed.
In order to solve the problem, a substrate processing apparatus of the present invention comprises a plate portion having a plurality of divided plates holding a substrate, and a heater heat-processing the substrate held by said plate portion.
According to the above structure of the present invention, the plate portion is formed by a plurality of divided plates, thus making the plate hard to break even through a drastic change in temperature, and increasing durability.
Another substrate processing apparatus of the present invention comprises a first plate portion having a plurality of divided and separated plates with a first space from each other and placed horizontally with a substrate, the first plate portion has a first surface and a second surface, the first surface holding the substrate, a heater for heat-processing the substrate held by the plate, and a gas supply mechanism supplying a first gas to the substrate through a first space between the adjacent divided plates of the first plate portion.
The apparatus further comprises a second plate portion having a plurality of divided and separated plates with a second space from each other and placed horizontally with the substrate and it is provided so that the substrate is being placed between the first plate portion and the second plate portion.
According to the above structure of the present invention, since a plurality of spaces are provided in the plate, the gas is supplied to the substrate through these spaces, therefore the gas is supplied to the wafer W uniformly throughout the surface.
According to one embodiment of the present invention, the apparatus further comprises a plurality of support members disposed so as to be inserted through the first space, holding the substrate with the predetermined space therefrom.
According to the above structure, with the structure in which the support members support the substrate, the load of the substrate is not exerted on the plate, thus making it possible to form the thickness of the plate to be thin to the limit. As a result, the plate can be formed to be thin, and thereby time taken to raise the temperature of the plate can be shortened, making it possible to reduce thermal capacity and contribute to energy conservation.
Further, for example, when the aforementioned gas is supplied to cool the substrate, the gas is supplied to the substrate through each space of the thin divided plates, and thereby the distance the gas flows through the space can be shorter in a thinner plate than a thicker plate, making it possible to reduce the flow of the gas and contribute to energy conservation.
According to one embodiment of the present invention, the thickness of the plate is 0.5 mm to 2.0 mm.
According to one embodiment of the present invention, the first space is formed to be gradually larger toward downstream compared to upstream where the first gas is supplied.
According to the above structure, uniform cool processing can be performed for the entire surface of the wafer W.
According to one embodiment of the present invention, surface areas of the divided plates of the first plate portion are formed to be gradually smaller toward downstream compared to upstream where the gas is supplied.
According to the above structure, uniform cool processing can be performed for the entire surface of the wafer W.
According to one embodiment of the present invention, the apparatus further comprises film members disposed attachably and detachably in the first space, having a plurality of holes.
According to the above structure, for example, by preparing two or more film members with a plurality of holes with different diameters, the supply of the gas to the substrate can be controlled by replacing them properly.
According to one embodiment of the present invention, the apparatus further comprises a guide member disposed at the second surface of the first plate portion guiding the supplied first gas into the first space.
According to the above structure, the gas can be supplied efficiently to the substrate.
According to one embodiment of the present invention, the guide member has a curving portion that gradually approaches the second surface of the first plate portion.
According to the above structure, for example, the temperature of the gas rises to an extent by the heat from the plate as the gas flows from upstream of the gas supply toward downstream, but the flow of the gas supplied to the substrate can be made larger toward downstream. Accordingly, uniform cool processing can be performed to the entire surface of the substrate.
Further, a substrate processing method of the invention comprises, holding a substrate on a first plate portion having a plurality of divided plates placed with a space from each other, heat-processing the substrate on the first plate portion, and separating the substrate from the first plate portion and supplying a first cooling gas to the separated substrate through a first spaces.